Some suggest that Billy Jenkins's default position – attaching a raucous Chicago electric-blues, R&B and gospel-style to lyrics about Ford Transits, jam sandwiches and life On (Catford) Broadway – is a gag at risk of running its course. But the south Londoner's eruptions of punk-improv guitar-playing, knack of assembling gloriously incompatible ingredients, and his underlying ire about the urban downside always cut through. I Am a Man from Lewisham is the surreal, chaotic and disarmingly charming result (think Chas and Dave or jaunty 1960s Ron Grainer TV themes interpreted by an Albert Ayler free-jazz band) of putting a disparate group of improvisers in a studio and letting them slug it out. Empirical saxophonist Nathaniel Facey does a nice line in R&B horn-wailing, violinist Dylan Bates mingles slewing atonality and Stéphane Grappelli elegance, and the deep brass of Oren Marshall's tuba and Gail Brand's trombone cushion the spiky outbursts of their partners, though Brand supplies plenty of abstract spikiness of her own. For all the furore, the ensembles are tight, and the themes often catchy.